TY  - RPRT
TI  - Reconnaissance of selected minor elements in surface waters of the United States, October 1970
AU  - W. H. Durum
AU  - John David Hem
AU  - Sumner Griggs Heidel
PY  - 1971
DO  - 10.3133/cir643
UR  - https://pubs.usgs.gov/publication/cir643
ID  - cir643
ER  -